Portable scaffolds



3 Sheets-Sheet 1 Feb. 2, 1965 c. w. PRossER PORTABLE scAFFoLDs Filed oct. 15, 1962 lNvENToR Clyde W. Prosser /qm/W j Feb. 2, 1965 c. w. PRossER PORTABLE scAFFoLDs 3 Sheets-Sheet 2 Filed Oct. l5, 1962 Feb. 2, 1965 c. w. PRossER PORTABLE scAFFoLDs 3 Sheets-Sheet 3 Filed Oct. l5, 1962 s.. m. F

United States Patent O 3,168,163 PURTABLE SCAFFOLDS Clyde W. Prosser, 217 Oriole Drive, Pittsburgh, Pa. Filed Get. 15, 1962, Ser. No. 230,595 i Claims. (Cl. 182--142) The present invention relates to portable scaffolds and particularly to a portable scaffold structure and elevator device for carrying material to the scaffold as the scaffold is moved within the work. The invention is particularly directed to scaffolds for use in vessels having an opening smaller than the interior diameter such as 1s found in `the Kaldo furnace, LD. vessels, Bessemer converters, blast furnaces and the like. These furnaces vary in diameter from top to bottom. The Kaldo furnace is typical of such structures. In the Kaldo furnace the opening is smaller than the diameter of the furnace intermediate the two ends and at the bottom is again reduced in a truncated cone-like form. Usually the bottom is removable so that access into the interior of the furnace may be had either from the top opening or from the bottom. vThe lining of these furnaces creates a very real problem in scaffold structure because of the need for a cantilever construction at the mid-area of the vessel. In the past, this has required continuous scaffolding; first, for the purpose of removing the old lining and then to place the new lining. This required that the scaffold be built and then torn down piece by piece as the old lining was removed and, thereafter, rebuilt piece by piece until the new lining was installed, and then finally torn down piece by piece for final removal. Since these furnaces must be relined frequently, usually after a weeks run, this scaffolding problem has become quite expensive and serious. In addition, there is the associatedfproblem of delivering supplies to the workmen and removing debris. This has in the past been done by conventional crane hooks lowering a container throngh the opening of the furnace down to the scaffold level. The workmen had to be removed in order to safely operate the crane or take the risk of serious injury if any slip occurred in the rigging carrying the materials and supplies.

I have invented a scaffold and elevator structure which overcomes the problems mentioned above and which is simple, inexpensive and readily portable. Preferably I provide a plurality of hollow, elongated scaffold members telescoping within one another, cooperating lock meansr on the top `and bottom of each said member adapted to hold the bottom of one member adjacent the top of the next smaller member in extensible position, support arms hinged at the top of the largest member adapted to be raised to the horizontal position and held there, removable grating means on said arms, means on the said largest member adapted to receive a crane hook whereby said member may be raised in the furnace, a plurality of spaced guides made up of telescoping guide members adapted to rest within one another, one of said guide members of each guide being attached to the largest scaffold member radially spaced from the center thereof and extending transversely from the plane of the top end thereof to form `an adjustable elevator shaft, cage means movable within said telescoping guide members and resiliently mounted guide wheels or rolls on said cage bearing on said telescoping guide members holding said cage centered therebetween. The spaced guides may be extended vertically upwardly from the top surface of the largest member or they may extend vertically downwardly through the opening in the bottom of a furnace. Preferably a loading platform is provided at the opposite extreme of the guides from the lCe scaffold at which point the cage may be loaded with supplies. The scaffold members may take the form illustrated in my copending application Serial No. 99,255 filed March 29, 1961, now Patent No. 3,058,543.

In the foregoing general description I have set out certain of the objects, advantages and purposes of my invention. Other objects, purposes and advantages will be apparent from a consideration of the following description and the accompanying drawings in which,

FIGURE 1 is a vertical section through a furnace and v scaold and elevator unit according to my invention with the scaffold in its lowest position;

FIGURE 2 is a section on the same line as that of FIGURE 1 but with the scaffold extended and the elevator guide removed;

FIGURE 3 is a vertical section through a furnace showing a second embodiment of my invention;

FIGURE 4 is a section on the same line as FIGURE 3 showing the scaffold partially extended;

FIGURE 5 is a section on the same line `as FIGURE 3 showing the scaffold fully extended; and

FIGURE 6 is a section through a furnace showing a third embodiment of my invention;

FIGURE 7 is a fragmentary section through a portion of the plurality of cylinders showing the removable locking pins;

FIGURE 8 is a fragmentary view of the side of the elevator cage and guide showing the resilient wheels;

FIGURE 9 is an enlarged vertical section of the elevator guide tubes and scaffold showing the screen assembly.

Referring to the drawings, I have illustrated a furnace 1f) of the Kaldo type having a truncated top terminating in a reduced opening 11 and a truncated bottom having a reduced opening 12 with a removable bottom 13. The furnace is lined with brickwork 14. A scaffold base 15 is adapted to rest on the removable bottom 13 or, alternatively, on an adjustable support later to be described. A plurality of cylinders 16, 17, 18, 19 and 20 are held together by a series of removable pins 16a, 17a, 18a and 19a which pass through openings in the sidewalls of the cylinder as described in my copending application Serial No. 99,255 land telescoped one about the other so as to rest on the base 15. Th largest cylinder 20 is provided with a lift bar such as is disclosed in my copending application. The lift bar is .adapted to receive a crane hook whereby the unit may be inserted in the furnace through the opening 11 and may be extended in the furnace. Each of the cylinders 16 through 20 are provided at the top and bottom with cooperating openings at the top and at the bottom through which lock pins may be inserted, all as described in my copending application. The top of the outer cylinder 20 is provided with hinged arms 21 adapted to fold against the sides of the cylinders. These arms when extended are adapted to receive removable grating sections 22 which form a work surface. A plurality of guides made up of telescoping units 23, 24, 25, 26, 27, 28 and 29 are spaced radially from the center of the scaffold members and are fixed at one end by attaching member 30 to the top V section 2f) of the scaffold. At the opposite end these guides yare fixed to a charging platform 31. Preferably the members are graduated from large diameter at each end to a smallest diameter in the middle of the guide. A cage 32 is 'adapted to slide between these guides on guide wheels or rolls 33 which are mounted on lever arms 33a pivoted to the side of the cage by a pivot pin 33h and urged toward the guide by a spring 33C as the cage is lifted. The cage is provided with a lift bar 34 adapted to receive a lift hook 35 on a cable 36 which may be from an overhead crane or from a similar source of lifting power.

Vfixed to the bottom guide member.

Screens 23a are fixedto member's'ZS. ,Telescoping screens are slidable dependent from screensr23a and terminate in bottom-'screens 29a The intermediate screens 24a, 25a, 26a, 2"?1y and' 28a may or may ynot be xed to their `corresponding guide members but only to guideways in the adjacent screens. vThese screenstelescope with the guide members forming a completely pro tected shaft. f 1 Y Y When it is desired to use the scaffold the scaffold' is Veach two adjacent top guider* those of FIGURES 4 and 5 and no further description of them is deemed necessary.

Telescoping guidemembersv 6o, 61, 62; 63,-64and Y 65 are'spaced radially'aroundthe axis of the scaffold within the scaffold at ther corners of opening 42'11.v The 'j yupper member 65' is xedtofthe top scaffold member and Vthe lower member 60 is fixed tothe base fof the scaffold support 417'b. Y A cage'66 moves the4 guide members lowered through the opening 11 by a crane hook. until the base 15 rests Von the bottom of the furnace.V The arms l on the upper scaffold memberZt). The pins between two I of the scaffold members whichfhave not been extended are removed. The' cable 36 is vrraised separating vthe two members from which'the pins have been removed until from a sitablepower source.

52b by means of cable 70 and hook 69. y

' When the scaffold is raised to a new position the guide y members yare extendedout of theirtelescopedrelation.` When the scaffold is lowered the guide members are .tele- 20.

and isprovided with spring loaded guide wheels or rolls bea'ring en the guide members to lhold the cage 66 within them.;v The cage V66jis provided with a lift bar 68 adaptedto Vreceive the'lifting hook V69 of` a lift :cable 70 Supplies are loaded on 'cage 66 vwithin .the scaffold support41b and raised to the level of the Work platform scoped.

While I have illustratedv and described certain preferred embodiments of my inventionit will be understood that the bottom of the larger approaches the top of the smallper member 20 is being raised Vthe guide members4 form- The' pins are then reinserted,jall as described in myy copending application Serial No. 99,255'. While the up'-V thislinven'tion maybe otherwise y.embodied Within the Yscope` of the following`claims. I

f 1. A portable scaffoldparticularly adaptedV for use in furnaces having an opening smaller than the interior diameter comprising a plurality of hollow elongated scaffold y membersv telesco'ping vwithin one another, cooperating ing the elevator shaft are bein'gcompressed 'along' with l their corresponding screensand' the lowerrnost member 29 f ,I support arms hinged kat the top of theflargest member and the corresponding Screen 29d-telescopes intovthe nextadjacent member 28 and V28a respectively.

operation is repeated each timek that itis necessary to raise the work platform.

In FIGURES 3,v 4 and 5=I havek illustrated' a second4 embodiment of my'invention in'which like elements lare identified with like numbers with the addition of, thel letter 41. In the figures, I have illustrated ya Kaldo support 41. The base 40 andthe top-tof the scaffoldsupport 41 are provided with an opening42 throughwhich access may be `had tothe interior of thez scaffold. The..

scaffold isfmadeup of a pluralityofy cylinders 41, 42, 43,

44; nestingone within the other as inthe case of VFIG-v URE 1. The largest of these scaffold members identified Yby the 4number 44 is provided with a lifting yoke 4S This same.V

lock -fneans on the top and bottom of eachfsaid member adapted to hold the bottom of one member adjacent the topvof'the next smaller member in extensible position,

adapted to be raised to the horizontal position and held there, removable grating means' on said arms, yoke means on vthe said largest member adapted [to receive a crane 'hook whereby said members'may be raised in the furnace,

a plurality'of spacedguides made up oftele'scoping guide members, 'one'ofsaid guide members of each guide being attached to the largest scaffold member radially spaced' v -fror'r'il the centerthe'reof and extending transversely from the .plane of the top endy thereof toform an adjustable' length elevato'r' shaft, cageymeans movable Within said telescoping guide members 1andresiliently mounted guide fixed ltothe periphery thereof.,` This lifting yoke carriesv a lifting rod 46 on link arms k47 swiveling on pinsy 48 ink the topof yoke 45. The liftingbar 46 is ,adapted to be engagedby a Vcrane hook 49 on a cable 50. The largest,

ofthe scaffold members 44v isalso provided with hinged'n arms 51V adapted to foldr againsttheside ofthe cylindeirv bottom of each saidrnember adaptedrtoyhold the bottom' wheels on said cage bearing on said,l telescoping 'guide members holding said cage centered therebetween.

2'. A'portableV scaffold particularly adaptedfor use in furnaces havingan opening smaller tha'nthe interior diameter ofgthe furnace and including a charging floor spaced from the scaffold, said scaffold comprising a plu# rality Yof hollow elongated scaffold members ytelescoping within one another,,cooperatingy lock means on the top and of one member adjacent the top of the next smaller `mem' ber in Yextensible position, supportarms hinged 4at, the top of theflargestJn'ie'mberv adapted toy bera'ised to the hori-l asillustrated inv FIGURES. These arms V51 areaadaptedto be extended, Ito receive 'a'plurality of removable gratings SZWhrich serveasa working surface. f -An elevator cage 53'is -adapted to be moved centrally throughthe adaptedto., receive a crane hook whereby saidzrr'lembers` lowered as described Cin-my copending Vapplication Serial f No. 99,255'.V

In theembodiment illustrated in FIGURE 6,71 have illustrated an apparatusidentical' with that'o'f El-IGURESQ- 4 and v5 but provided'witha telescoping elevatorshaft and?.V y cage. In this embodiment, -parts which are identical with those of FIGURES and 5 bear like/numbersrwith the suix b. YThe, furnace and scaffold are identicalwith 6() opening 42 inthe scaffold base 40 axially of the scaffold 'Y may be'raised'in the furnace, a plurality of spaced guides made up of` telescoping guide members, one' of said guide members ,of4 each guide being attached to the largest scaffold member radially/,spaced fromthe center, thereof and extending ,transversely from the plane ofv the top 1 end thereof, the guideimember remote from said one guideY member beingy attachedto the charging `floor to forman adjustable length elevatorshaft, telescopig screen meinbers surroundingrthe guide members andcorres'ponding inV numberthereto, .the'top and bottom screenmembers beingxed to' the topand bottom guide'members to telescope therewith, cage means movable within vsaid telescoping guide members and resiliently mounted guide'wheels- I on said cage bearing on said telescopingv guide members furnaces having an opening smaller than the interior diameter of the furnace and including a charging oor spaced above the furnace, said scaffold comprising a plurality of hollow elongated scalold members telescoping within one another, cooperating lock means on the top and bottom of each said member adapted to hold the bottom of one member adjacent the top of the next smaller member in extensible position, support arms hinged at the top of the largest member adapted to be raised to the horizontal position and held there, removable grating means on said arms, yoke means on the said largest member adapted to receive a crane hook whereby said members may be raised in the furnace, a plurality of spaced guides made up of telescoping guide members, the smaller diameter guide member of each guide being attached to the largest scaiold member radially spaced from the center thereof and extending transversely downwardly from the plane of the top end thereof and the largest guide member being removably attached to the charging oor to form an adjustable length elevator shaft, cage means movable within said telescoping guide members and resiliently mounted guide wheels on said cage bearing on said telescoping guide members holding said cage centered therebetween.

4. A portable scaffold particularly adapted for use in furnaces having an opening smaller than the interior diameter of the furnace and including a charging oor spaced above the furnace, said scaffold comprising a plurality of hollow elongated scaffold members telescoping within one another, cooperating lock means on the top and bottom of each said member adapted to hold the bottom of one member adjacent the top of the next smaller member in extensible position, support arms hinged at the top of the largest member adapted to be raised to the horizontal position and held there, removable grating means on said arms, means on the said largest member adapted to receive a crane hook whereby said members may be raised in the furnace, a plurality of spaced guides made up of telescoping guide members, one of said guide members of each guide being attached to the largest scaiold member radially spaced from the center thereof and extending transversely downwardly from the plane of the top end thereof and the guide member remote from said one guide member being removably attached to the charging iloor to form an adjustable length elevator shaft, cage means movable within said telescoping guide members and resiliently mounted guide wheels on said cage bearing on said telescoping guide members holding said cage centered therebetween.

References Cited in the tile of this patent UNITED STATES PATENTS 937,256 Minnich Oct. 19, 1909 2,009,846 Hirshfeld July 30, 1935 3,033,389 Abarotin May 8, 1962 3,058,543 Prosser Oct. 16, 1962 

4. A PORTABLE SCAFFOLD PARTICULARLY ADAPTED FOR USE IN FURNANCES HAVING AN OPENING SMALLER THAN THE INTERIOR DIAMETER OF THE FURNANCE AND INCLUDING A CHARGING FLOOR SPACED ABOVE THE FURNACE, SAID SCOFFOLD COMPRISING A PLURALITY OF HOLLOW ELONGATED SCAFFOLD MEMBERS TELESCOPING WITHIN ONE ANOTHER, COOPERATING LOCK MEANS ON THE TOP AND BOTTOM OF EACH SAID MEMBER ADAPTED TO HOLD THE BOTTOM OF ONE MEMBER ADJACENT THE TOP OF THE NEXT SMALLER MEMBER IN EXTENSIBLE POSITION, SUPPORT ARMS HINGED AT THE TOP OF THE LARGEST MEMBER ADAPTED TO BE RAISED TO THE HORIZONTAL POSITION AND HELD THERE, REMOVABLE GRATING MEANS ON SAID ARMS, MEANS ON THE SAID LARGEST MEMBER ADAPTED TO RECEIVE A CRANE HOOK WHERERBY SADF MEMBERS MAY BE RAISED IN THE FURNACE, A PLURALITY OF SPACED GUIDES MADE UP OF TELESCOPING GUIDE MEMBERS, ONE OF SAID GUIDE MEMBERS OF EACH GUIDE BEING ATTACHED TO THE LARGEST SCOFFOLD MEMBER RADIALLY SPACED FROM THE CENTER THEREOF AND EXTENDING TRANSVERSELY DOWNWARDLY FORM THE PLANE OF THE TOP END THEREOF AND THE GUIDE MEMBER REMOTE FROM SAID ONE GUIDE MEMBER BEING REMOVABLE ATTACHED TO THE CHARGING FLOOR TO FORM AN ADJUSTABLE LENGTH ELEVATOR SHAFT, CAGE MEANS MOVABLE WITHIN SAID TELESCOPING GUIDE MEMBERS AND RESILIENTLY MOUNTED GUIDE WHEELS ON SAID CAGE BEARING ON SAID TELESCOPING GUIDE MEMBERS HOLDING SAID CAGE CENTERED THEREBETWEEN. 